I've been thinking about this multisphere type and it just seems like it isn't worth it to play. That is, it doesn't seem to have any particularly strong matchups, or any sort of situation in which it shines compared to say, rushing and SP denying with Lawtia, or building a faster field with Gowen. Has anyone had any really strong success with it?

Yeah I've seen those files and they've colored me unimpressed. Sure, they look absolutely fearsome when they get going, but as someone that's faced that file with dolls, it doesn't hold up too well against heavy disruption. That is, it's SP intensive but very little protection against strategies that work to deny you resources (SP, sphere levels, units on the field, etc.), and against files that are also resource-intensive such as mid refess and such, it's more a sum of its parts.

I did a little with Galdire , and could see lots of possibilities with Lawt/Gowen. I buffed undeads and could have put dolls, Beltia, Dullin etc into it. I also made a poison ork file with Grebados and the new ork from set11. I made a poison merc file with the new merc cards from set 11.

Well it is worth it if you are using Francis or Shavara, because both are really strong cards. BKR will raise Francis AT too. Other than that it is just a collection of the strongest cards from both spheres and that is enough to win matches even if the player using it has no skill at all.

The other lawtia/gowen cards are stupid, look at Punishment Hole and Der Freischutz.

It's the same with other high-leveled units, not only narevez. That's why there is a card like charity, song of a hero, and others. If you can predict those kinds of situation, Narevez is awesome But yeah, it's hard to avoid Like the Hand of God.